SKYPE

Skype-to-Skype calls

Make calls on your computer to people who are signed in to Skype. Talk for as long as you like – and pay nothing. It’s free anytime, to any destination.

It’s also free to receive calls from your Skype contacts.

After a little research here are the benefits and some concerns:

Pros: Social tool to communicate to clients and employees
Cons: Lack of Security and Customer Service.

Features:
Calling
Video
Conferencing
IM & SMS
Admin Tool